In various chemical processes, gases and/or liquids need to pass from one tank to another. For example, in some spray drying processes, hot air from a ring main duct is injected radically into a concentric dryer shell through equally spaced ports. In such processes, the portions connecting the tanks (concentric bodies) has been known to fail or have unacceptable performance due to expansion differences of the two bodies resulting from their dissimilar temperatures. In addition, the connecting parts, or expansion joints, are typically at an angle different from the plane of the concentric bodies to allow for the drainage of fluids or slurries from one body to another. Expansion of angled components has lead to the design of relatively complicated expansions joints.
Traditionally these expansion joints are of two types, multi-layer flexible high temperature fabric and steel meshes that flex to allow for expansion differences or a bellows style steel expansion joint. These two types of expansion joints can have unacceptable performance for a variety of reasons. For example, uneven puckering of the flexible type causes air flow imbalance between the many connecting ports, chemicals attack the fabrics which are heat resistant but not chemical resistant and the pooling or damming of fluids in the bellows prevent complete gravity draining from one body into the other body. Also, due to the need for custom shape and dimension, these types of joints can be cost prohibitive.
Therefore, there is a need for a low cost expansion joint that would allow for different expansion rates of two or more concentric bodies. There is also a need for an expansion joint between two or more concentric bodies that can completely gravity drain without pooling or damming as the bodies expand and/or contract.